1. A diacritical mark (^) placed above a vowel in some languages to indicate a special phonetic quality: In some languages, a circumflex is above an alphabetical symbol in order to indicate a specific pronunciation, usually different from that of the unaccented letter. Circumflexes may be written over vowels as in French or over consonants as in Esperanto.
2. Curving around: Blood vessels are one kind of a circumflex in the body.
3. Etymology: from Latin circumflexus, past participle of circumflectere, "to bend around" + flectere, "to bend".